Main observation and conclusion Polymer-supramolecular double-network hydrogels(PS-DN hydrogels)often show much improved recovery rates than conventional double-network hydrogels because of the fast self-assembling pr...Main observation and conclusion Polymer-supramolecular double-network hydrogels(PS-DN hydrogels)often show much improved recovery rates than conventional double-network hydrogels because of the fast self-assembling properties,making them attractive candidates for tissue engineering and flexible electronics.However,as the supramolecular network is dynamic and susceptible to break under low strains,the overall mechanical properties of PS-DN hydrogels are still limited.Here,we report the mechanical properties for PS-DN hydrogels can be significantly improved by tuning the supramolecular network structures.A single amino acid change of the self-assembling peptide can tune the assembled structures from nanofiber to nanoribbon.Such a microscopic structural change can greatly increase the Young's modulus(107.4 kPa),fracture stress(0.48 MPa),and toughness(0.38 MJ·m^(–3))of the PS-DN hydrogels.Moreover,the structural change also leads to slightly faster recovery rates(<1 s).We propose that such dramatically different mechanical properties can be understood by the impact of individual peptide rupture events on the overall network connectivity in the two scenarios.Our study may provide new inspirations for combining high mechanical strength and fast recovery in double network hydrogels by tuning the supramolecular network structures.展开更多
基金supported mainly by the National Natural Science Foundation of China(Nos.11804148,11804147,11674153 and 12002149)the Natural Science Foundation of Jiangsu Province(Nos.BK20180320 and BK20180335)+1 种基金the Fundamental Research Funds for the Central Universities(Nos.020414380187,020414380148 and 020414380138)the Technological Innovation Foundation of Nanjing University(No.020414913413).
文摘Main observation and conclusion Polymer-supramolecular double-network hydrogels(PS-DN hydrogels)often show much improved recovery rates than conventional double-network hydrogels because of the fast self-assembling properties,making them attractive candidates for tissue engineering and flexible electronics.However,as the supramolecular network is dynamic and susceptible to break under low strains,the overall mechanical properties of PS-DN hydrogels are still limited.Here,we report the mechanical properties for PS-DN hydrogels can be significantly improved by tuning the supramolecular network structures.A single amino acid change of the self-assembling peptide can tune the assembled structures from nanofiber to nanoribbon.Such a microscopic structural change can greatly increase the Young's modulus(107.4 kPa),fracture stress(0.48 MPa),and toughness(0.38 MJ·m^(–3))of the PS-DN hydrogels.Moreover,the structural change also leads to slightly faster recovery rates(<1 s).We propose that such dramatically different mechanical properties can be understood by the impact of individual peptide rupture events on the overall network connectivity in the two scenarios.Our study may provide new inspirations for combining high mechanical strength and fast recovery in double network hydrogels by tuning the supramolecular network structures.